The Respiratory Burst Oxidase Homolog D (RbohD) Cell and Tissue Distribution in Potato-Potato Virus Y (PVY) Hypersensitive and Susceptible Reactions.

The respiratory burst oxidase homolog D (RbohD) acts as a central driving force of reactive oxygen species signaling in plant cells by integrating many different signal transduction pathways in plants, including incompatible interactions with pathogens. This study demonstrated the localization and distribution of RbohD in two types of potato-potato virus Y (PVY) interactions: Compatible and incompatible (resistant). The results indicated a statistically significant induction of the RbohD antigen signal in both interaction types. In the hypersensitive response (resistant reaction) of potato with a high level of resistance to the potato tuber necrotic strain of PVY (PVY), RbohD localization followed by hydrogen peroxide (HO) detection was concentrated in the apoplast. In contrast, in the hypersensitive response of potato with a low resistance level to PVY, the distribution of RbohD was concentrated more in the plant cell organelles than in the apoplast, resulting in the virus particles being present outside the inoculation area. Moreover, when compared to mock-inoculated plants and to the hypersensitive response, the PVY-compatible potato interaction triggered high induction in the RbohD distribution, which was associated with necrotization. Our findings indicated that RbohD and hydrogen peroxide deposition was associated with the hypersensitive response, and both were detected in the vascular tissues and chloroplasts. These results suggest that the RbohD distribution is actively dependent on different types of PVY -potato plant interactions. Additionally, the RbohD may be involved in the PVY tissue limitation during the hypersensitive response, and it could be an active component of the systemic signal transduction in the susceptible host reaction.